The latest edition of Home Energy magazine had an article on Chimney Balloons. Thought I would post to obtain your opinions. I was thinking on trying on my stinky fireplace. The $200 doors $100 Top of damper and traditional damper are no match to the stinky back drafting sooty odor.
It was tested with a blower door and seems to work.
I’ve never used one David but, if your chimney will accept it before or after the damper snugly, it looks like it may just work.
I recommend these quite a bit.
I recall a previouse conversation on this forum about the Chimney balloon damper in use with gas log sets. Here is a link to that :
The comment is way to the bottom of the thread.